Now: TYPE III AUDIO; Independent study.
Previously: 80,000 Hours (2014-15; 2017-2021) Worked on web development, product management, strategy, internal systems, IT security, etc. Read my CV.
Also: Inbox When Ready; Radio Bostrom; The Valmy; Comment Helper for Google Docs.
I strongly endorse what Rob said. Intense regular exercise is by far the best productivity and general well-being hack I’ve ever adopted. In my experience, once you get into it, it’s the opposite of a chore.
Second-best hack (for focus): Pomodoro Technique (use Tadam as your timer (Mac only))
Third-best hack (for reducing stress): regular mindfulness meditation (about 10 minutes / day, use Headspace to learn the basics).